Active lower leg engagement system

ABSTRACT

An active leg engagement system for a vehicle includes a selectively deployable leg-engaging member.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Ser.Nos. 61/910,270 and 61/910,265, both filed on Nov. 29, 2013, thedisclosures of which are incorporated herein by reference in theirentireties.

BACKGROUND OF THE INVENTION

Currently, in SUV's and light weight trucks, it is often difficult tomitigate leg injuries and prevent “submarining” of a pedestrian beneatha vehicle after contact between a moving vehicle and the pedestrian.This is due to higher bumper heights typical of these types of vehicles,and the difficulty of packaging a fixed low-mounted energy-absorbingmember due to vehicle styling demands, off-road performance needs, andother factors. Thus, a need exists for an active system designed todetect, catch and support the lower leg of a pedestrian during impactwith a SUV or light weight truck.

SUMMARY OF THE INVENTION

In one aspect of the embodiments described herein, an active legengagement system for a vehicle includes a selectively deployableleg-engaging member.

In another aspect of the embodiments of the described herein, a legengagement system for a vehicle is provided. The system includes adeployable leg-engaging member and is structured such that theleg-engaging member resides in a stowed position prior to activation.The system is also structured such that the leg-engaging member ismovable, prior to contact between a vehicle and a pedestrian, to adeployed position wherein at least a portion of the leg-engaging memberis positioned between a front bumper of the vehicle and a drivingsurface on which the vehicle resides.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain principles of theinvention.

FIG. 1 is a partial side view of a front end of a vehicle including aleg engagement system in accordance with one embodiment describedherein, shown in a stowed or pre-activation condition.

FIG. 2 is a partial perspective view of an underside of the front end ofthe vehicle of FIG. 1, showing the leg engagement system embodimentshown in FIG. 1.

FIG. 2A is a schematic view of a leg engagement system in accordancewith one embodiment described herein, shown in a fully-deployed orextended condition.

FIG. 2B is a schematic view of a leg engagement system in accordancewith another embodiment described herein, shown in a fully-deployed orextended condition.

FIG. 3 is the side view of FIG. 1, showing the embodiment of the legengagement system in a fully deployed or extended condition.

FIG. 4 is a schematic block diagram of a leg engagement system inaccordance with one embodiment described herein.

FIG. 5 is a schematic block diagram of a leg engagement system inaccordance with another embodiment described herein.

FIG. 6 is a schematic view showing a leg engagement system in accordancewith one embodiment described herein, in a fully deployed condition forengaging the leg of a pedestrian.

FIG. 7 is a schematic view of one embodiment of a leg engagement systemhousing to which other elements of the leg engagement system may beattached to facilitate installation in of the system a vehicle.

FIG. 7A is a schematic view of a leg engagement system housing to whichother elements of another embodiment of a leg engagement system may beattached to facilitate installation in of the system a vehicle.

FIG. 8A is a schematic view of a swing-type leg engagement system inaccordance with an embodiment described herein, shown in a stowed orpre-activation condition.

FIG. 8B is a schematic view of the swing-type leg engagement systemembodiment shown in FIG. 8A

FIG. 9A is a schematic view of a swing-type leg engagement system inaccordance with another embodiment described herein, shown in a stowedor pre-activation condition.

FIG. 9B is a schematic view of the swing-type leg engagement systemembodiment shown in FIG. 9A.

DETAILED DESCRIPTION

Like reference numerals refer to like parts throughout the descriptionof several views of the drawings. In addition, while target values maybe recited for the dimensions of the various features described herein,it is understood that these values may vary slightly due to such factorsas manufacturing tolerances, and also that such variations are withinthe contemplated scope of the embodiments described herein.

FIGS. 1-7 show various embodiments of a vehicle-mounted leg engagementsystem (generally designated 10). The leg engagement system incorporatesa leg-engaging member 12 which is movable to a predetermined position inrelation to a road or driving surface, so as to engage the leg of apedestrian below the knee when the vehicle contacts the pedestrian, oras soon as possible after contact between the vehicle and thepedestrian. In particular embodiments, leg-engaging member 12 ispositioned to contact the lower ½ of the tibia of an adult pedestrianpositioned in front of the vehicle bumper 99 when the system isdeployed. In the fully deployed position of the leg-engaging member 12,the leg-engaging member 12 aids in preventing “submarining” of apedestrian under the vehicle in the event of an impact. As used herein,the term “submarining” refers to movement of a pedestrian or a portionof a pedestrian under the front bumper and/or body of a moving vehicleafter contact of the vehicle with the pedestrian.

In the embodiments shown in FIGS. 1-5, leg engagement system 10 includesa movable energy-absorbing leg-engaging member 12. In one embodiment,the leg-engaging member 12 crescent-shaped and/or substantially followsor has the same curvature as the portion of the vehicle front bumperresiding just above the leg-engaging member when the member is in adeployed condition. Leg-engaging member 12 may be formed from anysuitable energy-absorbing material, for example, a foam material, apolymer, a rubber, a silicone, one or more metallic materials, etc.Leg-engaging member 12 may also be formed from an inflatable bag,membrane or receptacle, which may be inflated by a suitable gasgenerating system (for example, a squib or gas generating systemoperatively coupled to the receptacle) or other source of inflationfluid (for example, an air line operatively coupled to a reservoircharged by operation of a compressor) responsive to an activationsignal.

In a particular embodiment, a dimension H denoting a height or thicknessof the leg-engaging member along the surface of the member whichcontacts the leg of a pedestrian, is within the range 20 to 150millimeters, depending on the type of energy-absorbing material used inthe leg-engaging member, the available spacing between the drivingsurface and the vehicle bumper, and other pertinent factors.

In the embodiments described herein, the leg engagement system 10 is anactive mechanism, meaning that the leg-engaging member 12 is selectivelydeployable from a normally stowed or retracted (i.e., undeployed)condition (shown in FIGS. 1 and 2) to a fully deployed conditiondesigned to engage the leg of a pedestrian, responsive to the occurrenceof a predetermined condition or set of conditions. The fully-deployedposition is reached prior to contact between the vehicle and thepedestrian.

In certain embodiments, the leg-engaging member 12 is mounted onactuators in the form of one or more telescoping arms 14 operativelycoupling the leg-engaging member 12 to a portion of the vehicle. Theembodiments shown in FIGS. 1-5 utilize two spaced-apart telescoping arms14, with one arm connected to the leg-engaging member 12 proximate eachend of the member. However, any desired number of telescoping arms maybe used. Also, arms 14 may be connected to the leg-engaging member 12 atany desired location or locations along the member, depending on theoperational, structural or dimension al requirements of the particularapplication.

Referring to FIG. 2A, in one embodiment, each of arms 14 is in the formof a pneumatic or hydraulic piston-and-cylinder arrangement. A pistonrod 14 a is attached to the piston so as to move along with the piston(not shown). A portion of the leg-engaging member is attached to an endof each piston rod 14 a. In a known manner, activation of the legengagement system 10 causes pressurized fluid to be introduced into (orto flow within) the cylinders, resulting in movement of the pistons 14 balong interiors of their associated cylinders. Movement of the pistons14 b produces movement of the rods 14 a attached to the pistons, andalso a corresponding movement of the leg-engaging member 12 attached tothe ends of the rods 14 a, to the fully deployed position of theleg-engaging member.

FIG. 2A shows one example of a system employing actuatable arms 14 inthe form of piston-and-cylinder arrangements. In addition to arms 14 andleg-engaging member 12, this embodiment of the system includes acontroller 22 coupled to the arms 14 for controlling deployment of theleg-engaging member 12 in accordance with predetermined criteria, andone or more pressurized fluid sources and associated fluid flow controlmechanisms (including valving, solenoids, etc.) (generally designated51) operatively coupled to the controller 22 and to the cylinders 14 andstructured to provide pressurized fluid to the arms when desired.

Arms 14 may be structured, oriented and operatively coupled to thevehicle so that the parallel longitudinal or thrust axes P1 and P2 ofthe arms are directed toward or aligned with the final deploymentposition of the leg-engaging member 12, and so that the strokes of thearms, when actuated, move the leg-engaging member 12 into the desiredfully deployed position.

Pressurized fluid source(s) for the system may include, for example, areservoir charged by operation of a compressor and other known elementsfor a pneumatic system; a reservoir, pump, and other known elements fora hydraulic system; a gas generating system (for example, a knownmicro-gas generating system, or MGG) 97 as shown in FIG. 2B; or anyother suitable fluid source. A separate pressurized fluid source may beoperatively coupled to each cylinder 14. Alternatively, a commonpressurized fluid source may be coupled to both of arms 14.

Controller 22 may be a system controller already installed in thevehicle, or the controller may be a dedicated leg engagement systemcontroller.

The leg engagement system 10 may be activated by a signal received froma suitable sensor (or sensors) 20, or from controller 22 responsive to asensor input received by the controller 20. Sensor(s) are configured todetect the presence of a pedestrian in front of the vehicle out to atleast a distance sufficient to permit positioning of the leg-engagingmember in the leg-engaging position prior to contact of the vehicle withthe pedestrian, at vehicle speeds within the operational rangesdescribed herein. Types of sensors which may be used include knownradar, lidar, vision or any other suitable sensors configured to detectthe presence of a pedestrian in front of the vehicle and to generate aleg engagement system activation signal in time for the system to beactivated prior to contact between the pedestrian and the vehicle.Sensor(s) 20 used to detect the presence of the pedestrian may beexisting vehicle sensors or dedicated leg engagement system sensorsoperatively coupled to the leg engagement system controller 22 orcoupled directly to an element such as a gas generating systemstructured to supply pressurized fluid to the arms upon receipt of asuitable control signal.

In another embodiment (not shown), the telescoping arms 14 arespring-loaded. The arms are maintained in a stowed or retracted positionby a disengageable lock (using for example, a suitable solenoid) priorto deployment of the leg-engaging member 12. Suitable spring members areconfigured and operatively coupled to the arms so as to rapidly urge thearms to an extended or deployed position upon deactivation or release ofthe lock. The lock may be deactivated by a system actuation signalreceived from a controller. The controller signal is sent responsive toa signal from a sensor means (for example, a suitable radar, lidar,vision system, etc.) indicating that contact with a pedestrian may beimminent. This enables the spring-loaded arms to be extended and theleg-engaging member 12 moved to its fully-deployed position prior tocontact between the vehicle and the pedestrian. Upon deactivation of thelock, the arms extend, thereby positioning the leg-engaging member 12 inits final, fully-deployed position. The leg-engaging member 12 may laterbe reset (for example, manually) for subsequent use.

Referring to FIGS. 8A-9B, in other embodiments, the leg-engaging member12 is mounted on one or more swingable deployment arms 114 operativelycoupling the leg-engaging member to a portion of the vehicle. Theembodiments shown in FIGS. 8A-9B utilize two deployment arms, with onearm connected to the leg-engaging member 12 proximate each end of themember. However, any desired number of deployment arms may be used.Also, arms 114 may be connected to the leg-engaging member at anydesired location of locations, depending on the operational, structuralor dimension al requirements of the particular application. In addition,arms 114 may be rotatably coupled to housing 40 or directly to a portionof the vehicle (for example, frame 90). Also, in addition to controller22 and any required sensors, each of the embodiments shown in FIGS.8A-9B may include any pressurized fluid sources, valving, electroniccontrols, and/or any other components known in the art and required forfunctioning of the particular embodiment as described herein.

In the embodiments shown in FIGS. 8A-9B, arms 114 and the leg-engagingmember 12 attached thereto reside in a stowed condition as previouslydescribed, prior to activation of the leg-engagement system. However,rather than extending and retracting along longitudinal axes of the armsto deploy the leg-engaging member 12 as previously described with regardto arms 14, arms 114 are operatively coupled to the vehicle so as toswivel or rotate along a pre-defined arc relative to the vehicle todeploy the leg-engaging member 12.

FIG. 8A shows the swingable arms and the leg-engaging member 12 in astowed or pre-activation condition. In the embodiment shown in FIGS.8A-8B, after system activation, the deployment arms 114 move from theirstowed positions, swinging or rotating generally downwardly as indicatedby arrows MM to position attached the leg-engaging member 12 below thebumper as shown in FIG. 8B.

FIG. 9A shows the swingable arms and the leg-engaging member 12 in astowed or pre-activation condition in another embodiment of the system.In the particular embodiment shown in FIGS. 9A-9B, after systemactivation, the deployment arms 114 move from their stowed positions,swinging or rotating generally forwardly and downwardly as indicated byarrows M′M′ to position the leg-engaging member 12 below the bumper asshown in FIG. 9B.

Arms 114 may be operatively coupled to any suitable type of known rotaryactuator (generally designated 55), for example, a stepper motor andassociated sensors and/or position encoder and other hardware; a steppermotor and associated gear train, sensors and/or position encoder andother hardware; a known fluid power rotary actuator and associatedhardware, or any other suitable rotary actuator. Such actuators areavailable from a variety of vendors. A separate rotary actuator 55 maybe coupled to each of arms 114, or both arms may be rotated by a singlerotary actuator (as shown in FIG. 7A). The type of rotary actuator usedwill be specified according to such factors as the vehicle size envelopeinto which the leg engagement system is to be positioned, the torquerequirements for a particular design of leg-engaging member 12 androtating arms 114, and other pertinent factors.

The rotary actuator(s) 55 are operatively coupled to controller 22. Uponreceipt of an activation signal from the controller (and as describedelsewhere herein), the rotary actuator (s) operate to swing the arms 114downwardly and/or along the desired arcs until the leg-engaging member12 reaches its deployment position. If desired, one or more hard stops(not shown) may be operatively coupled to arms 114 to limit rotationmotion of the arms in a manner known in the art.

The leg engagement system is also structured to maintain theleg-engaging member 12 in the fully deployed position responsive toreaction forces exerted on the leg-engaging member by a pedestrian incontact with the member. In an embodiment using pressurized fluid tocontrol arm extension, the reaction forces may be absorbed in a knownmanner by the pressurized fluid in the arms.

In particular embodiment (for example, embodiments employing springloaded arms as described herein), a locking mechanism (not shown) may beincorporated into (or operatively coupled to) the leg engagement systemfor locking the leg-engaging member 12 in a deployed position ororientation. The locking mechanism may engage automatically when theleg-engaging member 12 reaches a fully-deployed position, and may bemanually disengaged to reset the position of the leg-engaging member 12for additional uses. Any of a variety of known mechanisms or methods maybe employed to maintain the leg-engaging member 12 in a deployedorientation or condition.

In one embodiment, a leg engagement system 10 as described above isbuilt into the structure of the vehicle. The mechanism for deploying theleg-engaging member 12 may be operatively coupled to a vehiclecontroller and/or to sensors installed in the vehicle duringmanufacture. In a particular embodiment, the leg-engaging member 12 isan inflatable member which resides stowed in a deflated condition insidea cavity formed in the vehicle bumper. An activation signal from asensor or controller triggers a gas generating system operativelycoupled to an interior of the leg-engaging member 12 so as to generatepressurized gases to inflate the member. After deployment, theleg-engaging member 12 may remain in the inflated or expanded conditionuntil the inflation gases are vented and the leg-engaging member 12 isreloaded into the bumper for subsequent use. The use of a rapidly-actinggas generating system enables relatively rapid deployment of theleg-engaging member 12 after the vehicle sensors 20 responsive todetection of a pedestrian in close proximity to the front of thevehicle.

The particular method used to position the leg-engaging member 12 priorto contact with a pedestrian will be determined by factors such as theavailable envelope size into which the leg engagement system may beinstalled; whether the leg engagement member is to deployed andretracted during normal vehicle operation, or deployed only when contactwith a pedestrian is deemed to be imminent; the response time of thesystem (from detection of a pedestrian to positioning of the legengagement member in the deployed position prior to contact with thepedestrian); the distance of the leg engagement member from the stowedposition to the deployed position, and other pertinent factors.

In an embodiment employing swingable or rotatable arms 114, the arms maybe structured to enable adjustment of the lengths of the arms (forexample, using a telescoping structure), or to enable variation of thedistance D9 (shown in FIG. 9B) between pivot locations of the arms onthe housing or vehicle, and the locations on the arms 114 at which theleg-engaging member 12 is attached. This provides additional flexibilityin positioning of the leg-engaging member 12, as described elsewhereherein.

In a particular embodiment, the leg engagement system includes a housing40 to which other components of the leg engagement system (for example,leg-engaging member 12, sensor(s) 20, controller 22, telescoping arms14, and any associated actuation mechanism (not shown), and any otherdesired component(s) may be mounted so as to form a module which may beaffixed to the vehicle frame or to another suitable portion of thevehicle. The housing enables mounting of the leg engagement systemcomponents thereto and fixing of the positions and orientations of thecomponents with respect to each other, to facilitate leg engagementsystem installation and proper operation of the system. The housing alsoenables the leg engagement system to be more easily retrofit onto anexisting vehicle. Mounting aids such as suitable spacers or mountingbrackets (not shown) may also be used to aid in attaching the housing toa given vehicle.

FIG. 7 is a schematic view of one embodiment of a housing 40 suitablefor mounting the other leg engagement system components thereon. In theembodiment shown in FIG. 7, housing 40 includes a first portion 40 a anda second portion 40 b structured so as to be slidable or otherwisepositionally adjustable with respect to the first portion when coupledto the first portion. In the embodiment shown, first and second portions40 a and 40 b are structured to permit a width W of the housing(extending perpendicular to a fore-aft axis of the vehicle when mountedin the vehicle) to be adjusted, and the housing portions secured inposition to maintain the desired width dimension. This adjustability ofthe housing width facilitates attachment of the housing to vehicleframes of various sizes. After the housing portions 40 a and 40 b havebeen fixed in position with respect to each other, other elements of theleg engagement system may be attached to the housing portions, usingfasteners, welds, or any other suitable method or methods. Housing maybe formed from any suitable material or materials (for example, metallicmaterials, polymers, etc.). The telescoping arms 14 may be attached tothe housing portions as shown and in accordance with one of theembodiments described herein.

FIG. 7A is a schematic view similar to FIG. 7, showing an embodiment inwhich swingable or rotatable arms 114 are attached to housing 40. In theembodiment shown in FIG. 7A, arms 114 are shown rotatably attached tohousing portions 40 a and 40 b. Arms 114 are rotated by a single rotaryactuator 55 operatively coupled to the arms and to housing 40 (ordirectly to the vehicle). Alternatively, each of arms 114 may beoperatively coupled to a separate rotary actuator.

In addition, the other elements of the leg engagement system may beattached to the housing portions prior to fixing of the housing portions40 a and 40 in position with respect to each other. This permits thehousing width W to be adjusted for attachment to portions of a specificvehicle, according to the requirements of a particular application andwith the other system elements already attached.

In another embodiment, the housing 40 is formed as a single, unitarystructure having a non-adjustable width W. The width dimension W isspecified so as to facilitate mounting of the housing to a frame orportions of a specific vehicle design.

As described herein, the module may incorporate or be operativelycoupled to an existing vehicle controller and/or sensors, or the modulemay be self-contained, incorporating its own controller and/or sensor(s)configured to actuate the leg-engaging member 12 prior to contactbetween the vehicle and the pedestrian, according to one or more of theoperational modes described herein.

In particular embodiments, the leg engagement system is structured suchthat the final positions and/or orientations of various components ofthe leg engagement system are adjustable with respect to the portions ofthe vehicle to which they are mounted. For example, cylinders 14 may beadjustable-stroke cylinders. Such cylinders are known in the pertinentart and are available from any of a variety of suppliers, for exampleTRD Manufacturing, Inc. of Machesney Park, Ill.

Also, where the cylinders 14 are attached to a housing 40 as describedherein, a portion of each cylinder may be rotatably attached to anassociated housing portion to permit adjustment of the cylinder angularorientation with respect to the housing, according to the requirementsof a particular application. The cylinder may be pivoted about therotatable connection to provide the desired angular orientation, andthen secured in this orientation using a pin, fasteners, or any othersuitable securement mechanism. Alternatively, rotatability of thecylinder with respect to the vehicle frame may be provided by directrotatable attachment of the cylinder to the vehicle frame.Alternatively, rotatability of the cylinder with respect to the vehicleframe may be provided by attachment of a suitable bracket to the frame,with respect to which the cylinder may be structured to rotate whencoupled thereto. This enables adjustment of the orientation of thecylinder with respect to the vehicle frame without the need to mount thecylinder on a separate housing.

In addition, where the cylinders 14 are attached to a housing 40 asdescribed herein, the cylinders may be mounted to associated portions ofthe housing so as to permit slidable movement of the cylinder withrespect to the housing along the axis (either axis P1 or P2, FIG. 2) ofextension of the telescoping arms. The cylinder body may be slidablypositioned along the housing according to the requirements of aparticular application and then secured in a given position using a pin,fasteners, or any other suitable securement mechanism. Alternatively,slidability of the cylinder with respect to the vehicle frame may beprovided by attachment of a suitable bracket or other hardware to theframe, along which the cylinder may be structured to slide when coupledthereto. This enables adjustment of the location of the cylinder alongthe deployment axis without the need to mount the cylinder on a separatehousing.

In addition, the leg-engaging member 12 may be rotatably connected tothe ends of cylinders 14 or arms 114 (using for example, a pin), so asto permit adjustment of the angular orientation of the leg-engagingmember 12 with respect to the projected path of loading by thepedestrian, and in accordance with the final deployed position of themember. The leg-engaging member 12 may be oriented as needed and securedin the desired orientation using any suitable method.

Other portions of the system may also be positionally and/orrotationally adjustable so as to provide flexibility with regard toinstallation of the system in a vehicle, while ensuring that the fullydeployed position of the leg-engaging member 12 is attained afteractivation of the system. More specifically, the adjustability describedprovides flexibility in the positioning and attachment of the systemcomponents to the vehicle so as to ensure that the leg-engaging member12, when fully deployed, resides at a location D2 with respect to thevehicle bumper and at a location D1 with respect to the driving surface,as defined by the dimensional ranges described herein.

In one mode of operation, the leg engagement system 10 is configured fora single activation. The system must then be manually reset orreconfigured for a subsequent use, by a user or by a service center. Oneexample of such an embodiment is shown in FIG. 2B, where a gasgenerating system (for example, a suitable micro-gas generator or MGG)provides the pressurized fluid source for actuation of arms 14. After asingle activation of the system and deployment of the leg-engagingsystem, the gas generating system must be replaced by a service center.

In another mode of operation, the leg engagement system 10 isautomatically resettable and reusable (i.e., the system is resettablewithout the need for action by a user to reset the system). One exampleof such an embodiment is shown in FIG. 2A, where fluid flow to eitherside of the piston in the cylinder 14 is controlled by operation of thecontroller 22 on the valving 51 controlling fluid flow to the portionsof the cylinder 14. Direction of the pressurized fluid to either side ofthe piston 14 b controls extension and retraction of the arms 14 in aknown manner.

Referring to FIGS. 1-3, prior to activation of the leg engagementsystem, the leg-engaging member 12 is stored in a retracted orundeployed condition along an underside of the vehicle prior toactivation of the leg engagement system. This prevents contact betweenthe leg-engaging member and the driving surface R when the vehicle isdriven off-road or along uneven road surfaces. The leg engagement system10 is also structured and installed so as not to increase the length ofthe vehicle when the leg-engaging member is in a stowed position (asshown in FIGS. 1 and 2).

The height above the road surface of the leg-engaging member 12 prior toactivation of the system will generally be specified by the vehiclemanufacturer, and may be set according to the system stroke length, anypackaging constraints governing positioning and/or installation of theleg engagement system, the intended use of the vehicle when leg-engagingmember 12 is stowed, and other pertinent factors so as to ensure thatthe height D1 of the leg-engaging member 12 above the road surface whendeployed is within the desired range for operational effectiveness, aspreviously described. However, in the embodiments described herein, thedistance of the leg-engaging member 12 from the driving surface prior toactivation (i.e., in the stowed condition) will always be greater thanthe distance D1 of the leg-engaging member 12 from the driving surfacewhen deployed.

In a particular embodiment, the leg engagement system 10 is structuredso that when the leg-engaging member 12 is in the stowed condition, theentire leg-engaging member 12 is positioned above a plane defined by alower edge of the vehicle bumper, as defined by a plane B1 shown in FIG.3. This aids in reducing aerodynamic drag that might result fromportions of the leg-engaging member 12 extending below the bumper whenthe leg-engaging member 12 is in the stowed position.

In a particular embodiment, the dimension D1 denoting the height abovethe road surface of the leg-engaging member 12 when the leg-engagingmember is in a fully-deployed and locked condition, is within the range150 to 930 millimeters.

Referring to FIG. 3, the dimension D2 denotes a distance of a verticalplane G passing through a forward-most surface F of the leg-engagingmember 12, from a vertical plane P passing through a forward-mostsurface of the front bumper 20 when the leg-engaging member 12 is in afully-deployed and locked condition. Thus, in a leg-engaging member 12which follows the contour of the bumper 99, the distance between plane Ppassing through surface F and following the contour of the bumper and aplane G passing through surface F and following the contour of theleg-engaging member, will be constant or substantially constant alongthe entire length of the leg-engaging member. The distance D2 of theforward-most contact surface of the leg-engaging member 12 from thebumper plane P may need to be adjusted in order to accommodateoperational requirements in different bumper and vehicle designs. Itcertain embodiments, it may be desirable to achieve coplanarity orsubstantial coplanarity of plane P with plane G (for example, as shownin FIG. 2A). In a particular embodiment, the leg-engaging member plane Gis coplanar with plane P within a range of +/−50 millimeters when theleg-engaging member 12 is in a fully-deployed and locked condition.

As described herein, the deployable arms 14 are structured to move theleg-engaging member 12 from a stowed position (shown in FIGS. 1 and 2)to the fully deployed position shown in FIG. 3 within a desiredpredetermined time after activation of the leg engagement system 10. Inone embodiment, the arms 14 are activated to position the leg engagementmember 12 only when contact between the vehicle and a pedestrian isdeemed to be imminent. In such cases, the leg engagement member 12 mustbe deployed relatively rapidly, and the employed should be capable ofpositioning the leg engagement member 12 in the desired leg engagementposition prior to any contact between the vehicle and the pedestrian, Inparticular embodiments, the system is configured to position the legengagement member 12 in the desired leg engagement position within 300milliseconds of receipt of an actuation signal from a sensor orcontroller.

In another embodiment, the system is configured so that the leg-engagingmember 12 resides in a stowed position when the vehicle is travelling ata speed within the range 0-10 MPH and also when the vehicle is travelingat a speed above 25 MPH. The arms deploy when the vehicle reaches aspeed above 10 MPH to position the leg engagement member 12 in its legengagement position, and revert to the stowed condition when the vehiclereaches a speed above 25 MPH. In this mode of operation, if desired, theleg engagement member 12 may be deployed more slowly than required foran imminent contact with the pedestrian. For purposes of thisembodiment, the controller may be operatively coupled to any sensor orother means (for example, a speedometer or wheel speed sensor) useablefor measuring or calculating vehicle speed. The particular range ofvehicle speeds over which the leg engagement member 12 is deployed maybe determined by the vehicle manufacturer.

In another particular embodiment, the system is configured to deploy theleg engagement member 12 to the desired position when contact betweenthe vehicle and a pedestrian is deemed to be imminent, but only when thevehicle is traveling at a speed within a predetermined range (forexample, between 10 to 25 MPH, inclusive).

In a particular embodiment, the system is provided with a systemoverride or disabling means which enables the leg engagement system 10to be disabled under certain conditions (for example, during off-roaddriving, when a snow plow is attached to the front of the vehicle, orfor any other particular vehicle use). In one embodiment, the disablingmeans comprises a switch or button in the passenger compartment whichenables a user to shut off the leg engagement system 10. In anotherembodiment, the disabling means comprises a switch attached to thehousing 40 or provided under the vehicle hood (labeled VH in thedrawings), and also operable by a user. Operation of the disabling meansmay signal to the controller that no activation signals are to betransmitted to the actuating arms 14 until the leg engagement system isswitched on or re-enabled, or otherwise prevent transmission ofactivation signals to the arms 14.

FIG. 4 is a block diagram of a leg engagement system which is normallyin a stowed condition, and which is deployable responsive to detectedimminent contact between the vehicle and a pedestrian. In thisembodiment, sensor or sensors 20 incorporated into or operativelycoupled to the leg engagement system 10 detect the presence of apedestrian in front of the vehicle. A sensor signal is transmitted to acontroller 22, which processes or evaluates the sensor signal inaccordance with predetermined leg engagement system activationprotocols. Responsive to the result of the signal processing, thecontroller generates an activation signal which is transmitted to thearms 14 or to any associated fluid control mechanism, resulting inactuation of the arms 14 to deploy the leg engagement system 12 prior tocontact between the vehicle and the pedestrian.

In an alternative embodiment shown in FIG. 5, the arms 14 are activatedresponsive to a signal sent directly from the sensor to the arms 14 orto an associated fluid control mechanism. A signal from a sensor or asuitable controller activates the gas generator, which actuates thepiston-and-cylinder arrangements. The piston rods then extend from thecylinders to deploy the leg-engaging member 12. Other deployment methodsare also contemplated. Any deployment mechanism used should be able to,responsive to an activation signal, deploy the leg-engaging member 12rapidly enough to ensure full deployment prior to contact between thevehicle and the pedestrian.

Referring to FIG. 6, an embodiment of the leg engagement system 10 maybe incorporated into a vehicle-mounted pedestrian safety system. FIG. 6shows a schematic diagram of one exemplary embodiment of such a safetysystem installed in a vehicle. In FIG. 6, a leg engagement system 10 inaccordance with an embodiment described herein may be secured to thevehicle 9 beneath and/or behind the front bumper as previouslydescribed. When activated, the leg-engaging member 12 of the systemdeploys toward the front of the vehicle in the direction indicated byarrow Z, to a position where the lower leg of a pedestrian may beengaged as previously described.

Also, as seen in FIG. 6, when the leg engagement system is fullydeployed, the leg-engaging member 12 complements or acts in conjunctionwith bumper 99 and/or other vehicle features designed to engage thelower body of the pedestrian during contact, to aid in supporting theleg at multiple locations and maintaining alignment of the leg from thehip region down to and including the tibia. For example, bumper 99and/or other front-mounted vehicle features may be designed to supportthe leg down to and including the knee joint. By engaging the portion ofthe leg below the knee to help prevent this portion of the leg frombeing forced beneath the front of the vehicle, the deployed leg-engagingmember 12 helps prevent excessive bending of the leg at the knee, whichaids in reducing injury to knee ligaments.

Leg engagement system 10 may be in operable communication with a sensor20 which is in communication with a processor or controller (ECU 22) aspreviously described. Controller implements a known algorithm thatsignals actuation the gas generating system or valving controllinganother pressurized fluid source operatively coupled to each of arms 14.As previously described, activation and/or control of the pressurizedfluid source(s) operatively coupled to each of arms 14 may be based onany desired criteria, for example, detected actual or imminent contactof the vehicle with a pedestrian 98, and/or any other desired criteria.

As utilized herein, the terms “approximately,” “about,” “substantially”,and similar terms are intended to have a broad meaning in harmony withthe common and accepted usage by those of ordinary skill in the art towhich the subject matter of this disclosure pertains. It should beunderstood by those of skill in the art who review this disclosure thatthese terms are intended to allow a description of certain featuresdescribed without restricting the scope of these features to the precisenumerical ranges provided. Accordingly, these terms should beinterpreted as indicating that insubstantial or inconsequentialmodifications or alterations of the subject matter described areconsidered to be within the scope of the invention.

It should be noted that the term “exemplary” as used herein to describevarious embodiments is intended to indicate that such embodiments arepossible examples, representations, and/or illustrations of possibleembodiments and such term is not intended to connote that suchembodiments are necessarily extraordinary or superlative examples.

The terms “coupled,” “connected,” and the like as used herein means thejoining of two members directly or indirectly to one another. Suchjoining may be stationary (e.g., permanent) or moveable (e.g., removableor releasable). Such joining may be achieved with the two members or thetwo members and any additional intermediate members being integrallyformed as a single unitary body with one another or with the two membersor the two members and any additional intermediate members beingattached to one another.

References herein to the positions of elements, for example “top,”“bottom,” “above,” “below,” etc., are merely used to describe theorientation of various elements in the FIGURES. It should be noted thatthe orientation of various elements may differ according to otherexemplary embodiments, and that such variations are intended to beencompassed by the present disclosure.

It will be understood that the foregoing descriptions of the variousembodiments are for illustrative purposes only. As such, the variousstructural and operational features herein disclosed are susceptible toa number of modifications, none of which departs from the scope of theappended claims.

What is claimed is:
 1. An active leg engagement system comprising: aselectively deployable leg-engaging member; at least one arm operativelycoupled to a portion of a vehicle, the at least one arm operativelycoupling the leg-engaging member to the portion of the vehicle; and ahousing structured for attachment to a portion of the vehicle, whereinthe at least one arm is operatively coupled to the housing and thehousing is structured such that a width dimension of the housing isadjustable to a first width and securable at the first width.
 2. The legengagement system of claim 1 wherein the leg-engaging member isstructured to reside in a stowed position prior to activation, andwherein the leg-engaging member is structured to be movable, prior tocontact between a vehicle and a pedestrian, to a deployed position so asto engage a leg of a pedestrian at a location below a knee of thepedestrian when the pedestrian is positioned in front of a front bumperof the vehicle.
 3. The leg engagement system of claim 2 wherein thesystem is configured to move the leg-engaging member to the deployedposition upon detection of the pedestrian in front of the front bumperof the vehicle.
 4. The leg engagement system of claim 2 wherein thesystem is configured to move the leg-engaging member to the deployedposition when a speed of the vehicle reaches 10 miles per hour.
 5. Theleg engagement system of claim 4 wherein the system is configured toreturn the leg-engaging member to the stowed position when the vehiclespeed exceeds 25 miles per hour.
 6. The leg engagement system of claim 1wherein the system comprises a pair of spaced-apart arms, each armoperatively coupling the leg-engaging member to an associated portion ofthe vehicle.
 7. The leg engagement system of claim 1 wherein the atleast one arm is a telescoping arm in the form of a piston-and-cylinderarrangement.
 8. The leg engagement system of claim 7 wherein thepiston-and-cylinder arrangement is an adjustable-strokepiston-and-cylinder arrangement.
 9. The leg engagement system of claim 1wherein the at least one arm is a rotatable arm.
 10. The leg engagementsystem of claim 9 further comprising at least one rotary actuatoroperatively coupled to the at least one rotatable arm and configured forrotating the at least one arm upon activation of the leg engagementsystem.
 11. The leg engagement system of claim 1 wherein the at leastone arm is operatively coupled to the housing so as to be movable alongthe housing to a first position with respect to the housing andsecurable in the first position.
 12. The leg engagement system of claim1 wherein the housing is structured such that a width dimension of thehousing is adjustable to a first width and securable at the first width.13. The leg engagement system of claim 1 wherein the at least one arm isoperatively coupled to the housing so as to be rotatable to a firstorientation with respect to the housing and securable in the firstorientation.
 14. The leg engagement system of claim 1 wherein the legengagement mechanism is structured such that, when the leg-engagingmember is in the stowed condition, the entire leg-engaging member ispositioned above a plane defined by a lower edge of the front bumper.15. The leg engagement system of claim 1 further comprising a disablingmeans enabling a user to manually disable the system.
 16. The legengagement system of claim 2 wherein the system is structured such thata first vertical plane passing through a forward-most surface of theleg-engaging member when the leg-engaging member is in a deployedposition condition, is coplanar with a second vertical plane passingthrough a forward-most surface of the front bumper.
 17. A pedestriansafety system including a leg engagement system in accordance withclaim
 1. 18. A vehicle including a leg engagement system in accordancewith claim
 1. 19. A vehicle including a pedestrian safety system inaccordance with claim 1.